The Ukrainian military on Monday renewed its assault on this rebel-held city, even as international investigators in the region were trying to secure the remains of all 298 passengers and crew killed in the downing of a Malaysia Airlines jet.
Explosions and artillery fire could be heard in central Donetsk from the direction of the city’s train station and airport, and a spokesman for the pro-Russian rebels said there was also fighting near the central market. Portions of the city 40 miles from the crash site were closed off.

“This is a planned offensive,” said a Ukrainian military spokesman, Vladislav Seleznev. The military is trying to push rebels away from the airport, he said. “Aviation and artillery are not aiming at civilian residences. Their only aim is to block the terrorists and fighters.”
At the same time, Ukrainian Prime Minister Arseniy Yatsenyuk continued to build a case being made by Washington and Kiev that pro-Moscow separatists and Russian forces worked hand in hand in acquiring and operating the missile battery believed to have been used to shoot down the jetliner Thursday. He said the rebels alone did not have the technical ability to operate such sophisticated equipment. He implicated Russia in aiding them and called for an international investigation to establish the facts.
“Drunken guerrillas cannot manage this system,” Yatsenyuk told reporters Monday in Kiev. “They need to work in cooperation with another radar system that we don’t have in Ukrainian territory, and we want an international investigation to get the real facts of who targeted” the flight.
Yatsenyuk said 31 international experts, including two from the United States, have landed in the eastern Ukrainian city of Kharkiv. The government was still trying to establish a safe humanitarian corridor to take them through rebel-held territory and to the crash site.
He declined to comment on whether the government had launched a fresh offensive to retake Donetsk.
Amid growing international outrage, diplomats pressed the United Nations Security Council to vote Monday on a resolution demanding that pro-Russian separatists grant unfettered access to the crash site in eastern Ukraine as the rebels continued to hinder officials on the ground seeking to secure the bodies of the 298 victims.
Australian Prime Minister Tony Abbott echoed growing outrage over rebel actions to limit access to the site and their mishandling of bodies. He called on Russia, which has a veto at the Security Council, not to block the motion being proposed by his nation.
“There is no doubt that at the moment the site is under the control of the Russian-backed rebels,” Abbott told reporters in Canberra. He said the situation at present was tantamount to “leaving criminals in control of the crime scene.”
Late Sunday, a Ukrainian committee said limited teams of rescuers had found 251 bodies and 86 fragments of bodies, which were loaded onto two trains, according to Reuters news agency. But the trains were being held at a railway station in the town of Torez by rebels who were refusing to let it leave.
International observers from the Netherlands and the Organization for Security and Cooperation in Europe (OSCE) on Monday visited refrigerated train cars at the Torez station where the bodies were being kept. The observers were under heavily armed guard.
Michael Bociurkiw, an OSCE spokesman, said it remained unclear when the rail cars containing the bodies would move and where they would go. He said renewed fighting in Donetsk on Monday had possibly damaged the tracks, adding a possible new complication.
“We were told by rebels it has caused some damage to railway system,” he said of the latest fighting. “That is a crucial development in the sense that with the airport inoperable, and if the train station is inoperable, that will cut off Donetsk even further.”
In a video statement issued early Monday, Russian President Vladimir Putin said some local and emergency workers had been allowed onto the crash site, but he conceded that “this is not sufficient” and called for the establishment of a safe, humanitarian corridor for investigators. He called for renewed dialogue to restore peace in region, yet he also seemed to push back against the global accusations implicating rebels.
“At the same time, no one should and has the right to use this tragedy to achieve their own political goals,” Putin said.
Perhaps suggesting a slight backtracking, Putin stopped short in his statement of once again tactically blaming the Ukrainian government, as Russian officials have largely done in the wake of the crash. Instead, he seemed to blame the resumption of fighting after a cease-fire ended late last month.
“I am confident this tragedy would definitely not have happened if the hostilities had not resumed in eastern Ukraine on June 28,” he said.
European leaders — who have thus far imposed limited sanctions on Russia — continued to threatened far tougher action if Putin did not up the pressure on the rebels to cooperate. After a coordination of efforts between the leaders of Germany, Britain and France, foreign ministers from the European Union were set to meet on Tuesday to decide on fresh steps.
Any move to enact truly sweeping sanctions could bring a swift response from Moscow. Thus far, European nations have been leery of taking tough steps, due in part to their lucrative economic ties to Russia. On Monday, George Osborne, Britain’s chancellor of the exchequer — or treasury secretary — told the BBC that London was ready to take an economic hit because doing nothing would be worse.
“Sanctions will have an economic impact, and we are prepared to undertake further sanctions,” Osborne said. He said that the effect of “allowing international borders to be ignored, of allowing airlines to be shot down — that’s a much greater economic hit for Britain, and we’re not prepared to allow that to happen.”
A rebel leader, Andriy Purgin, told Russia’s Interfax news service on Monday that separatist groups would arrange for the bodies to be sent to Kharkiv.
“So far the victims’ bodies remain in the railcars of the refrigerator train at the Torez station,” Purgin said. “They will be sent to Kharkiv only after international experts — Dutch, Malaysian or the Red Cross representatives — arrive at the scene. They are to accompany the train with the bodies. We are ready to add a separate railcar for them.”
He said his group was preparing to greet arriving international investigators in Donetsk.
“This morning, our colleagues were to meet the first group of international experts,” said Purgin. “Gradually, experts started coming over. We broke the shield the Ukrainian side put in their way; we are expecting Red Cross experts to arrive tomorrow.”
Purgin also has denied the allegations that separatists are being supplied with military hardware from Russia. “I have not seen this hardware,” he said. “Not one of the 150 items that are being attributed to us. Had we had this hardware, the military situation would have been completely different.”
A Dutch military plane carrying coffins arrived Monday in the provincial capital of Kharkiv in preparation for the transfer and removal of the bodies.
Kharkiv, which is about 180 miles northwest of Donetsk, is emerging as a regional center to coordinate the repatriation of the passengers’ remains and to investigate the crash.
Local officials said four agents from Interpol and Europol, the European Union’s law enforcement agency, also arrived Monday. An international coordinating delegation, primarily from the Netherlands along with a few Germans, held a brief news conference in which they announced their presence and said they have work to do without answering more specific questions. The Dutch plane carrying the coffins also brought seven forensics experts to Ukraine, according to the Kharkiv regional government.
Ukrainian President Petro Poroshenko said he had ordered his government to assist in the “immediate return of the bodies home.” A spokesman for his cabinet said a total of 282 bodies had been located by Monday afternoon, along with 87 body fragments.
There were no indications that Kharkiv would serve as anything more than a transit point for the bodies en route to the Netherlands. Local officials said, however, that they were ordered by the government to prepare for any family members who want to be in Kharkiv as their loved ones make their final journey home.
Nataliya Drozd, a spokeswoman for the government’s crisis center, said they have lined up more than 400 rooms in 10 hotels for relatives and located three empty factory warehouses where airplane parts could be collected and stored.
They also are staffing a small call center that relatives can telephone to find hotels or get contacts for any of the international groups involved in the investigation. But since the call center started Saturday, the only queries have come from Ukrainians volunteering to act as interpreters and psychological counselors, and from reporters, said Marina Kravchenko, an English-language schoolteacher who volunteered to answer the phones that rang only once in about half an hour.